The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A228761 Primes of the concatenated form 149x149 for some number x. 1
1496149, 1497149, 1499149, 14915149, 14924149, 14925149, 14928149, 14931149, 14942149, 14945149, 14951149, 14976149, 14985149, 14991149, 149124149, 149127149, 149132149, 149135149, 149150149, 149153149, 149159149, 149162149, 149171149, 149175149, 149187149, 149192149 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Sequence is infinite. - Charles R Greathouse IV, Sep 03 2013
LINKS
FORMULA
Primes of the form parse(cat(149,x,149)).
EXAMPLE
a(1)= 1496149 is a term in the sequence as it is a prime of the form abcxabc: abc are square digits 1,4 and 9 in order.
MAPLE
with(StringTools): KD:= proc() local a, b; a:= 149; b:=parse(cat(a, x, a)); if isprime(b) then RETURN(b): fi; end: seq(KD(), x=1..1000);
MATHEMATICA
With[{c={1, 4, 9}}, Select[Table[FromDigits[Join[c, IntegerDigits[n], c]], {n, 200}], PrimeQ]](* Harvey P. Dale, Jan 14 2015 *)
PROG
(PARI) for(x=1, 1e3, if(ispseudoprime(t=eval(Str(149, x, 149))), print1(t", "))) \\ Charles R Greathouse IV, Sep 03 2013
CROSSREFS
Sequence in context: A128837 A297881 A335289 * A206060 A251973 A236499
KEYWORD
nonn,base,less
AUTHOR
K. D. Bajpai, Sep 03 2013
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 16 16:46 EDT 2024. Contains 373432 sequences. (Running on oeis4.)